Aiming arrangement

ABSTRACT

A gun turret of a tank, equipped with acoustic and optical aiming devices. The acoustic device is used to bring the gun to bear in the general direction of a target from which a noise comes, whereafter the optical aiming device, which may include an infrared searchlight, is turned on. In this way, the initial target acquisition and the preliminary aiming are done by passive means, the active aiming means being used only after the preliminary aiming and being needed for only a very short time.

United States Patent Heinz Hermes Wedel;

Helmut Hinterthiir, Hamburg-Blankenese; Arnold Otto, Hamburg; Klaus Dietrich Thieme, Wedel; Heinz Westhoff, Braunschweig, all of Germany [72] Inventors [21 Appl. No. 788,354 [22] Filed Aug. 19, 1968 [45] Patented Oct. 19, 1971 [73] Assignee Licentia Patent-Verwaltungs-G.m.b.H.

Frankfurt am Main, Germany 32 Priority Aug. 19, 1967 Germany [3 1 L 57246 [54] AIMING ARRANGEMENT 6 Claims, 2 Drawing Figs.

[52] U.S. Cl 340/16 R,

89/40 B, 89/41 s, 356/141 51 Int.Cl 00153/00 [50] Field ofSearch 340/16,16 R; 343/6 IR; 56/141,152, 4, 5; 89/40 B, 41 B, 41 S, 41 E [56] References Cited UNITED STATES PATENTS 2,256,787 9/1941 Lazar 340/16 X 2,416,155 2/1947 Chubb 340/16 X FOREIGN PATENTS 448,516 6/1936 Great Britain 340/16 Primary ExaminerRichard A. Farley At!0rneySpencer & Kaye ABSTRACT: A gun turret of a tank, equipped with acoustic and optical aiming devices. The acoustic device is used to bring the gun to bear in the general direction of a target from which a noise comes, whereafter the optical aiming device,

which may include an infrared searchlight, is turned on. In this way, the initial target acquisition and the preliminary aiming are done by passive means, the active aiming means being used only after the preliminary aiming and being needed for only a very short time.

PATENTEU UCTIQIBYI 3,614,723.

IN VENTORS HEINZ HERMES, HELMUT HINTHERTHUR ARNOLD OTTO, KLAUS DIETRICH THIEME, HEINZ WESTHOFF AIMING ARRANGEMENT BACKGROUND OF THE INVENTION The present invention relates to an aiming and detecting device and, in particular, to a device of this type suitable for use in armored vehicles in which rotatable, optical means are provided for taking a bearing and aiming a gun about the vertical axis.

Modern military combat vehicles are designed so as to insulate the occupants of the vehicle from the outside world and thus provide maximum protection against so-called ABC- weapons (atomic, bacteriological and chemical). Visual communication between the interior and exterior of the vehicle is established by means of optical and/or electronic viewing means, the latter including, for example, closed-circuit television systems. In order to make the vehicle itself as unnoticeable as possible to an enemy, the viewing means, and particularly the means by which targets are acquired and a weapon carried by the vehicle is trained on the target, should be passive so as to prevent premature detection by the enemy. At the present time, the state of the art is such that passive viewing means are not too reliable for use in the dark, so that normally searchlights or spotlights, operative in the visible or invisible (infrared) spectrum are relied on. Since the light beam emitted by an infrared searchlight can be seen with the help of infrared viewers, it behooves the crew of an armored vehicle equipped with this type of searchlight to use it as little as possible.

SUMMARY OF THE INVENTION Accordingly, it is the primary object of the present invention to provide a way in which the time interval during which a searchlight, be it one with visible or infrared light, is used for the purpose of target acquisition and aiming, can be kept to a minimum.

With the above object in view, the present invention resides, basically, in the provision of a support mounted for rotation about a vertical axis, there being optical means arranged on this support for rotation therewithv At least two acoustic receivers are also arranged on the support and are spaced laterally apart from each other, the perpendicular bisector of the line joining the two receivers extending in the same direction as the optical axis. Means are connected to the outputs of the receivers for deriving therefrom a signal which is a function of the angle between the direction from which a noise comes and the perpendicular bisector. In this way, if the support is the gun turret of a tank, the gunner can rotate the turret about the vertical axis until the optical axis of the optical means is generally aligned with the direction from which the noise comes. The optical means, such as a searchlight, can then be turned out.

BRIEF DESCRIPTION OF THE DRAWINGS H6. 1 is a perspective and partly schematic illustration of one embodiment of an arrangement according to present invention wherein the acoustic receivers are mounted on a turret of a tank, while H6. 2 shows another such embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and first to FIG. 1 thereof, the same shows rotary tank turret 11 carrying a gun 10, the same having associated with it active optical means, such as a searchlight 12, which is preferably an infrared searchlight, and an optical gunsight 18. The passive acoustic ranging means has two laterally spaced-apart acoustic receivers 13 and 14 are located at the two opposite sides of the turret, the arrangement being such that the perpendicular bisector of the line joining the two receivers extends in the same direction as the optical axis of the optical means associated with the gun. This optical axis is shown by the phantom line 12a which is the axis along which the searchlight throws out its beam of light. The outputs of the receivers 13 and 14 are connected to a control circuit 15 which includes the usual power supply and which derives from the signals coming in from the receivers a signal which itself is a function of the angle between the direction from which a noise comes and the perpendicular bisector between the two receivers, the latter, as aforesaid, extending in the same direction as the optical axis 120. The output of the control circuit 15 is connected to an indicator 16 which gives a visual indication of the amplitude and algebraic sign (right or left) of the difference signal; for example, the indicator can include a pointer whose deflection from straight up" indicates the angle between the direction from which the noise comes and the direction in which the gun 10 is pointed.

If desired, the indicator 16 may be structurally integrated, into the optical gunsight 18 by means of which the gun 10 is aimed visually, so that the relative bearing of the origin of the noise signal is correlated to the optical axis of the gunsight.

The output of circuit 15 is also applied to a set of earphones l7 worn by the gunner; if desired, the connection is such that the signal coming from the left acoustic receiver 14 is fed to the left earphone while the signal coming from the right acoustic receiver 13 is fed to the right earphone so that the gunner will receive a two-channel or stereophonic signal by means of which he will be able to rotate the turret 11 until the signals coming into both earphones are of the same strength, which will occur when the turret, and hence the gun 10, is trained dead ahead to the source of origin of the noise being picked up by the acoustic receivers whereupon the optical axis 12a will be alignedin practice quite accurately-with the direction from which the noise comes.

It will be appreciated that the circuit 15 and the indicator 16 are conventional, and need therefore not be described in detail. For example, the circuit 15 can be arranged to determine the difi'erence between the transit times of the incoming noise signal and apply an appropriate signal to indicator 16 so as to deflect the pointer.

in operation, when a noise will be picked up by the receivers 13, 14, the gunner can detect the direction from which the noise emanates and rotate the turret 11 until the gun 10 is pointed at least generally in this direction. During this time, the searchlight will be switched off, and will not be switched on until the gun is already practically on target. Once the light has been switched on, the final sighting can be accomplished visually through the gunsight 18. In practice, the preliminary acoustic aiming will allow the turret to be trained with sufficient accuracy on the target so that the same will be in the light beam of the searchlight once the same is turned on.

The acoustic receivers 13, 14 are, preferably, directional receivers, and will be directionalized, as shown by phantom axes 13a and 14a, in the direction in which the gun 10 is pointed. In this way, the so-called lambiguity is avoided, i.e., the gunner will not be misled and point the gun in precisely the opposite direction from whence the noise comes. Moreover, noises coming from the wrong direction will be attenuated.

Instead of providing directionalized acoustic receivers for use as the receivers 13 and 14, there may be provided two convention nondirectional receivers together with a third acoustic receiver 21 which is arranged on the above-mentioned perpendicular bisector of the line joining the two basic receivers l3, l4 and is spaced from this line. The output of this receiver 21 is likewise connected to the control circuit 15 where the signal from receiver 21 is processed so as to enable the gunner to determine whether a given noise comes from the front of the turret (as viewed in FIG. 1) or the rear. This can be done, for example, by piping the output of receiver 21 into the earphones to give a particular aural signal when the noise comes from the front, which signal would be missing if the noise came from the rear. Alternatively, or additionally, the signal from receiver 21 is applied to the indicator 16 to enable that instrument to give an unambiguous relative bearing of the direction from which the noise comes.

In practice, the earphones may also be used as part of the internal or external communication system of the vehicle. When the earphones are used for the purpose of acoustic direction finding, they may be used to determine not only the direction but also the type of noise being picked up.

The various acoustic receivers will, in practice, be so constructed as to be sufficiently sensitive to pick up very low sound levels emanating from outside the vehicle, while they must be sufficiently rugged to withstand the loud noises caused upon firing of the gun 10, as well as the other rigors to which a vehicle of this type is subjected.

In FIG. 2, the optical and acoustic means described above are arranged not on the tank turret directly but on a rotary platform 19 which is mounted on the turret 11 and which is shown as carrying a second weapon, such as a machine gun 20. In this way, the machine gun can be trained acoustically in the direction from which a noise emanates, whereafter the infrared searchlight can be turned on and the machine gun can be aimed visually. When desired, however, the platform 19 can be blocked with respect to the turret 11, whereupon the optical and acoustic means can be utilized in conjunction with the gun 10.

it will thus be seen that, thanks to the present invention, the weapon can be trained-at least approximatelyon a target from which a noise emanates, this being done acoustically and thus passively, in the sense that the acoustic detect'mg means can themselves not be detected by the target. Then, after the target has been acquired and the weapon has been trained in the general direction of the target, the nonpassive aiming means, i.e. the searchlight-which during the preliminary aiming will automatically have been directed in the general direction of the targetis turned on so as to enable the gunner to make the final adjustment in the bearing of the weapon. It will be appreciated that, since the weapon has been preliminarily trained solely by passive aiming means, the short interval of time during which the nonpassive aiming means need be utilized is very short, so that the enemy will have very little time in which to take cover or to take any other defensive or offensive countermeasures.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations.

We claim:

I. The combination which comprises:

a. a support mounted on an armored vehicle for rotation about a vertical axis;

b. active optical means for final sighting of an associated weapon, said means defining an optical axis and being fixedly arranged on said support with the weapon for rotation therewith;

c. passive acoustic ranging means for preliminary aiming and having at least two acoustic receivers also fixedly arranged on said support for rotation therewith and being spaced laterally apart from each other, the perpendicular bisector of the line joining said two receivers extending in the direction of said optical axis; and

d. means connected to the output of said receivers for deriving therefrom a signal which is a function of the angle between the direction from which a noise comes and said perpendicular bisector, thereby to enable an operator to rotate said support about said vertical axis until said optical axis is generally aligned with the direction from which the noise comes.

2. The combination defined in claim 1 wherein the vehicle is a tank and said support is a tank turret.

3. The combination defined in claim 1 wherein the vehicle is a tank having a turret, and wherein said support is a rotary platform carried by said turret.

4. The combination defined in claim 1 wherein each of the acoustic receivers is a directional receiver.

5. The combination defined in claim 1, further comprising a third acoustic receiver arranged on said bisector and spaced from said line joining the first-mentioned two receivers; and means connected to said third receiver for enabling the operator to make a sense determination and thereby avoid lambiguity.

6. A method for target finding with a device mounted on an armored vehicle, comprising the steps of:

a. preliminary aiming with a passive acoustic ranging device having at least two acoustic receivers arranged on a support mounted for rotation on the annored vehicle and being spaced laterally apart from each other, a perpendicular bisector of the line joining the two receivers being defined; the aiming step including the step of deriving a signal from the outputs of the receivers which is a function of the angle between the direction from which a noise comes and the perpendicular bisector, thereby to enable the operator to rotate the support about its verti cal axis until the perpendicular bisector is generally aligned with the direction from which the noise comes; and

b. final sighting with an active optical device mounted on the support along with an associated weapon for rotation therewith and defining an optical axis which is parallel to the perpendicular bisector, the preliminary aiming step permitting the final sighting to be of a minimum time duration. 

1. The combination which comprises: a. a support mounted on an armored vehicle for rotation about a vertical axis; b. active optical means for final sighting of an associated weapon, said means defining an optical axis and being fixedly arranGed on said support with the weapon for rotation therewith; c. passive acoustic ranging means for preliminary aiming and having at least two acoustic receivers also fixedly arranged on said support for rotation therewith and being spaced laterally apart from each other, the perpendicular bisector of the line joining said two receivers extending in the direction of said optical axis; and d. means connected to the output of said receivers for deriving therefrom a signal which is a function of the angle between the direction from which a noise comes and said perpendicular bisector, thereby to enable an operator to rotate said support about said vertical axis until said optical axis is generally aligned with the direction from which the noise comes.
 2. The combination defined in claim 1 wherein the vehicle is a tank and said support is a tank turret.
 3. The combination defined in claim 1 wherein the vehicle is a tank having a turret, and wherein said support is a rotary platform carried by said turret.
 4. The combination defined in claim 1 wherein each of the acoustic receivers is a directional receiver.
 5. The combination defined in claim 1, further comprising a third acoustic receiver arranged on said bisector and spaced from said line joining the first-mentioned two receivers; and means connected to said third receiver for enabling the operator to make a sense determination and thereby avoid 180*ambiguity.
 6. A method for target finding with a device mounted on an armored vehicle, comprising the steps of: a. preliminary aiming with a passive acoustic ranging device having at least two acoustic receivers arranged on a support mounted for rotation on the armored vehicle and being spaced laterally apart from each other, a perpendicular bisector of the line joining the two receivers being defined; the aiming step including the step of deriving a signal from the outputs of the receivers which is a function of the angle between the direction from which a noise comes and the perpendicular bisector, thereby to enable the operator to rotate the support about its vertical axis until the perpendicular bisector is generally aligned with the direction from which the noise comes; and b. final sighting with an active optical device mounted on the support along with an associated weapon for rotation therewith and defining an optical axis which is parallel to the perpendicular bisector, the preliminary aiming step permitting the final sighting to be of a minimum time duration. 